Sunday, March 16, 2014

Field Activity #7: Visual Introduction to Unmanned Aerial Vehicles

Introduction:

In this field activity, I was given the opportunity to see a few different unmanned aerial vehicles in action. While the term seems to imply something very mechanical, in reality it can be something as simple as a kite. Four different methods were experimented with including two rotary wing aircraft as well as a kite and a rocket. 

Methods:

Rotary Wing Aircraft #1

The first UAV (seen in Figure 1) belonged to Dr. Joe Hupy. As you can see it hovers using the the three double-blade propellers. This is field undergoing a lot of experimentation with different methods. Thus, this is not the only model by any means.

Figure 1: This rotary wing UAV belonging to Dr. Joe Hupy hovers utilizing three double-blade propellors. 

Just to give you an idea of the technology involved, this rotary wing aircraft is powered by a battery. It also needs to carry a sensor (or multiple sensors depending on the needs of the operation). This craft is equipped with a canon digital camera as well as various other sensors (as seen in Figure 2). Payload is very important for each UAV because the aircraft will need to be able to carry the weight of all necessary sensors and so forth and still maintain flight per operation specifications. This requires careful pre-planning to assess these needs, develop an appropriate UAV, and arm it with the necessary devices.

Figure 2: This figure shows the battery and sensors attached to the UAV comprising its payload.

It is also important to have experiencing operating a UAV when doing field work. This rotary wing aircraft is controlled by a remote control (as seen in Figure 3). Without knowing how to handle the aircraft under its current specifications, it could be lost altogether. Each time payload is adjusted, the aircraft will need to adjust as well. Very few (if any) parts of using UAVs can be done haphazardly. This aircraft experienced a payload change and had to undergo in-flight calibration to assess the capability for the craft to manage the weight and get the weight properly balanced for accurate flight guidance by an operator.

Figure 3: This figure shows the remote control used to operate and guide the rotary wing aircraft.

Figure 4: This figure shows an operator using a remote control guiding the rotary wing aircraft

Just to give you an idea of what this aircraft looks like in flight I have included a video (as seen in Figure 4). I have to admit, it is a little bit unnerving to see something like this if you are not aware of who is operating it and for what purpose. These are items to take not of when undertaking a mission using a UAV.


Figure 4: This figure shows Dr. Hupy's rotary wing aircraft in flight.

Rotary Wing Aircraft #2

The second UAV we witnessed in action was also a rotary wing aircraft. This model was developed by the operator (seen with his aircraft in Figure 5). As opposed to the first one, it hovers utilizing 6 single-blade propellers.

Figure 5: This figure shows a rotary wing aircraft with its creator in the background. It hovers using 6 single-blade propellers.

This particular model was much faster than the first rotary wing aircraft (as seen in Figure 6). Both of them had approximately the same amount of flight time. 


Figure 6: This figure shows the take-off for the rotary wing aircraft. 

Kite

Next, a kite was put up into the air. This is not a cheap kite you buy at Wal-Mart. It is basically industrial strength (for a kite) in order to withstand conditions as well as handle a payload in order to carry a sensor.

Figure 7: This figure shows the kite that operates as a UAV by being armed with a sensor.

Once the kite is in flight, a sensor is basically run up the string (as seen in Figure 8) in order to capture aerial footage.

Figure 8: This figure shows a sensor being run up the string of the kite in order to capture aerial footage.

This may seem a rudimentary method of capturing aerial footage, but it can be highly effective in the right setting. Wind is obviously the most crucial factor to monitor if this method is used. Without enough wind, your operation will be grounded. Too much wind can also be an adverse factor.

Figure 9: This figure shows the kite attached with an aerial sensor in flight.

Rocket

As I mentioned, in this fledgling industry a lot of experimentation exists. this is especially true as each new mission presents unique nuances that need to be addressed. Dr. Joe Hupy had the idea of attaching a small sensor to a rocket (as seen in Figure 10. This would be a relatively inexpensive option to obtain aerial footage if it works. 

As you can imagine, the element of control seen in both kite and rotary wing aircraft flights is not really an option with this method. Its used would be minimal, but with a small mission scope, could prove extremely useful. 
Figure 10: This figure shows Dr. Joe Hupy attaching a small sensor to a rocket for the purpose of colleecting aerial footage.

Unfortunately this trial did not work out. Both engines in the rocket did not fire properly and the flight time was very short lived. This is the nature of experimentation, and it will be be carried out again. 

Conclusion:

There are many methods by which aerial images can be obtained. This exercise was just an example of some them. Each method presents unique capabilities and challenges that must be accounted for in mission planning.











Sunday, March 9, 2014

Field Activity #6: Microclimate Geodatabase Construction for Deployment to ArcPad

Introduction:

It is very important to establish and understand the relationship between field work and ArcGIS. Properly utilized, ArcGIS can enhance the work being done in the field; failing to utilize ArcGIS properly can actually create more difficulty in the collection and transmission of data captured in the field.

The basis for a good relationship between ArcGIS and field work can be condensed down to pre-planning. Taking the time to develop the needs of your project and mold ArcGIS tools around those needs is essential to efficient and accurate data collection.

One of the keys to building this relationship is geodatabase construction. In preparation for the creation of a microclimate map of the UWEC campus, this exercise will focus in building a properly formatted geodatabase considering all the variables associated with the project. After providing some general information about a geodatabase, I will go over each of these two elements, pre-planning and geodatabase construction, in detail.

Geodatabase Overview:

When importing spatial and attribute data into ArcMAP, it must be "contained" in something that the program can read and display.

Two different formats exist to do this: geodatabases and shapefiles.

Shapefiles (.shp) were originally created in the 1990's for use with the original ESRI program called ArcView. They store the primitive geometric data types of points, lines, and polygons. However this format lacks the capacity to store topological information. In other words, they do not possess the ability for the user to specify rules and conditions pertaining to the data. Pertaining to field work, this makes it much more time consuming for an operator to monitor the data collection process in order to avoid errors. As a general rule, shapefiles are larger, slower and less flexible than file geodatabases.

Geodatabases (.gdb), store the same type of information found in shapefiles as feature classes and can contain many such classes. In addition to being smaller, faster, and more flexible, geodatabases have one major advantage over shapefiles, the ability to utilize data management capabilities offered in ArcMAP. Topological information (rules) can be applied to the geodatabase, and each feature class within it, based on the range and type information they will contain.

This acts as a management tool for data being captured in the field. For instance, if the range of a particular type of data is well known, the range can be applied to a feature class essentially disallowing numbers outside of this range. This can help to avoid data entry mistakes while doing field work.

Five reasons to use geodatabases have been outlined by ESRI as listed below:
  1. A geodatabase is a uniform repository for geographic data, and it is scalable. This makes it easier to manage and access.
  2. Data entry and editing are more efficient. By storing GID data in a geodatabase, you are able to apply rules and constraints on the GIS data to reduce the chances of error being introduced into the datasets.
  3. The geodatabase can model advanced spatial relationships. The geodatabase not only defines how data is stored, accessed, and managed, but it can also implement and model spatial relationships of features in a feature class or between feature classes.
  4. The geodatabase has multiuser capabilities. You can have two or more users accessing the data at the same time, simultaneously making edits.
  5. The geodatabase enables your GIS data to be integrated with information technology systems.

Pre-Planning:

Because of the advantages offered through the use of a geodatabase, they are an invaluable tool for fieldwork if properly employed. This is entirely contingent upon careful pre-planning by operators. Careful analysis should take place defining the scope of all data pertaining to the mission.

To guide thinking for the pre-planning process as it pertains to geodatabases, think in terms of domains, ranges, and measurement units.

These are the categories used in ArcMAP for geodatabase creation and will be discussed further in the next section, Geodatabase Construction. For now, just think of a domain as the general kind of data being collected (tree diameter, hill slope, wind direction, etc.), and ranges as the bounds that can be applied wherein all data collected will fall. Measurement units should be much simpler to understand, still it is important to specify how your data is being measured. Is distance being measured in meters or feet?

While this is not an exhaustive list of questions to be asked, the following can act as a guide for how to engage in pre-planning for the purpose of constructing an effective geodatabase.
What are the variables (domains) pertaining to your mission?
Can the data collection of these variables be bounded into a range of possible entries?
What are the measurement units for each variable?
If the variable records nominal data can it be grouped into categories?

Specifying the answers to these questions will provide you with the information you need to build an effective geodatabase.

Microclimate Pre-Planning Example

To provide an idea of how pre-planning for a geodatabase should be carried out. I will answer the questions I have listed and provide answers pertaining to the microclimate geodatabase I am preparing for use in a future exercise.

In the following weeks, I will be building a microclimate map of the UWEC campus. This will be done by measuring designated variables at various locations on campus and entering their records into a GPS device. In order to ensure accurate and efficient data collection, I will build a geodatabase with my specified domains and fields. This information will be imported to the GIS device. I will then be able to enter my data into pre-assigned fields based on my planning. 

What are the variables (domains) pertaining to your mission?

Because my mission will be to create a microclimate map, I will be identifying weather-related variables to be entered as domains.

The variables I have identified are group name or number, temperature, time of day, wind direction, wind speed, relative humidity, dewpoint, and snow depth. 

*It is also a good idea to include a general notes field for any information that does not fall into your variable categories.*

Can the data collection of these variables be bounded into a range of possible entries?/

What are the measurement units for each variable?/

 If the variable records nominal data can it be grouped into categories?

A common sense approach can help guide you to identify the ranges, numerical units, and categories for your variables. You want to allow for data that may not fit your initial expectations while disallowing numbers that are clearly outside of the range of possibility. For instance, temperature in Eau Claire in January and February have been extremely cold. However, it is not out of the realm of possibility to see temperatures much warmer than expected. I want to comfortably set my range to encompass the entire realm of possible outcomes and exclude such possibilities as 150 degrees Fahrenheit.

Some data may not be numbers but nominal data. For instance, wind direction data will not be entered as a number but in words like northeast or southwest. Other information for other studies may be categorical in nature such as identifying how many of a certain kind of tree are in a certain area. Then, you would want to establish the potential range of categories. In Eau Claire, WI desert cacti can be ruled out as a potential category.

Once you have identified these elements pertaining to the data for your mission, you can proceed to building a geodatabase. I will explain this process in the next section.

Geodatabase Construction:

Any time you are working with a new tool, becoming familiar with terminology, definitions, and locations can often be an arduous process. Building a geodatabase is a relatively simple process once you have become familiar with the basics. If it seems difficult at first, it is most likely just a matter of allowing yourself time to acclimate to what you are doing.
First, the program in which to set up a geodatabase is ArcCatalog. Open this program to begin.
Create a New File Geodatabase

Step 1: Within the catalog tree to the left of the screen, right click on the folder connection you would like to store the new geodatabase in. Select New and File Geodatabase (as seen in Figure 1).
  

  
Figure 1: This figure outlines the steps in ArcCatalog to take in order to create a new geodatabase.

Step 2: You will then have the opportunity to name your geodatabase (as seen in the highlighted area in figure 2). As a general rule avoid long names and spaces. In order to create space between two items, use underscore instead.

Figure 2: This figure shows the area where you can enter the name of your geodatabase (as seen in the highlighted area).

 Add Domains from Pre-Planning

Step 3: Next, you want to enter the domains you defined in your pre-planning as well as specify ranges and units of measurement for each domain. To do this, first right click on your newly created geodatabase, and select properties.


Figure 3: This figure shows you how to select Properties in order to be able to enter your domains from pre-planning.

Step 4:The Database Properties screen will appear (as seen in Figure 4). Select the Domains tab at the top-left of this screen and you will be able to enter your domains.

Figure 4: This figure shows the layout of the Database Properties screen. This is where you will enter your domain information.

Step 5: To begin entering your domains start in the Domain Name field. Here you want to include a general title based on the variable. The Description area can include any information that helps you define the variable. Think of what you might want to remember when you are collecting data. For instance, I am not used to thinking in military time when recording the time. I will be setting the range up in way where military time is required. To ensure I remember that in the field, I have included that information in the description (as seen in Figure 5).

Figure 5: This figure shows the domain names and descriptions entered for the microclimate geodatabase. The domain name is the general description of the variable; the description can contain any information pertinent to you in the field.

Step 6: Next, move down the screen in the same database properties window to choose your Field Types. This exact term has not been previously mentioned but pertains to both the range and measurement unit specifications developed in pre-planning. 

When you click on the default setting, text, to the right of Field Type, a drop-down menu will appear containing the following seven options: short integer, long integer, float, double, text, and date. Four of them relate to specific types of numerical data. Examples and applications pertaining to each data type are available from ESRI (as seen in Figure 6).

Figure 7: This table from ESRI outlines the range of usage for the four numeric data types.

Two data types are not included in this table because they are not for numerical data. I will explain their uses below.

Date: This data type is self-explanatory. However, it can include dates, times or dates AND times. The default setting for this data type consists of mm/dd/yy and hh:mm:ss fields for date and time, respectively.

Text: While this may also seem self-explanatory, the text field can include both letters AND numbers for use in recording street names, etc. It can be used for any variable not identified with numeric values. 

Another option is to "code" textual information with numeric values to save storage space in the geodatabase. In order to take this step, pre-planning must include setting up an accurate coded system.  

Step 7: If you have specified any ranges to bond your data by, you can do this by selecting the field to the right of Domain Type. A drop-down menu will allow you to select either coded values or range. Coded values is the default setting. By choosing range, a space for Minimum Value and Maximum Value becomes available (as seen in Figure 8).

Figure 8: This figure shows the minimum and maximum value field appearing below domain type when the domain type is switched to range.

Step 8: If you have chosen to included coded values for any of your domains you can enter them at the bottom of the database properties screen in the coded values table. Make sure the appropriate domain name is active when you do this or you could apply it to the wrong domain. In the Code field, specify the number attached to a certain value or category. Under the Description heading, specify the exact values attached to the code (as seen in Figure 9).

Figure 9: At the bottom of this figure entries for coded values can be seen including the code and description.

Step 9: You now have completed all the step necessary for the creation of your geodatabase. Simply select Apply at the bottom right of the Database Properties. 

Create a Feature Class in ArcCatalog

As mentioned in the Geodatabase Overview, geodatabases store data in feature classes. Information is added to a map by adding feature classes to the geodatabase. You will need to create a new feature class.

Step 1: Right click on your new geodatabase; navigate to New, and Feature Class (as seen in Figure 10). 

Figure 10: This figure outlines the process of creating a new feature class within your database in ArcCatalog.

Step 2: A window will appear allowing you to name your new feature class as well as set the Type of features you would like to be stored in the feature class in the drop down menu (as seen in Figure 11). The type of features you choose should be based on the way your data will be displayed on a map. If you will simply be storing point data, choose point features, if you are outlining building locations and basic area, choose polygon features, etc.

Figure 11: This figure shows the New Feature Class screen. Here you will enter the name of your feature class as well as set the feature type from the drop-down menu under Type.

Once this has been completed select Next at the bottom-right of the New Feature Class window.

Step 3: The next screen that will appear allows you to choose a coordinate system in which to display your data when you are ready to map (as seen in Figure 12). It is very important to choose a coordinate system that displays your particular area the best way possible. The UWEC campus is located in Eau Claire, WI will be best viewed in the NAD 1983 UTM Zone 15N and will be used to display my microclimate map.

Figure 12: this figure shows the screen where you will select the coordinate system to display your new feature class. More details about the coordinate system you select are listed under Current Coordinate System at the bottom of the screen.

Once you have selected your coordinate system, choose Next at the bottom-right of the Feature Class Properties window.

Step 4:  The next screen will allow you to adjust the XY tolerance if you so desire. For this exercise, no changes were needed. To move from this step, select Next at the bottom-right of the Feature Class Properties window.

Step 5: The next screen will allow you to specify the database storage configuration. In most cases, you will choose the Default setting. To move from this step, select Next at the bottom-right of the Feature Class Properties window.

Step 6: The next screen to appear will have headings of Field Name and Data Type at the top (as seen in Figure 13). Underneath these headings you will place your Domain categories and their coinciding data types.

Figure 13: This figure shows the table where you will enter the domains and data types specified when you created your geodatabase based on your pre-planning.

When you have entered all of your domains and field types, click Finish at the bottom right of the New Feature Class Window. This new feature class will be used, through ArcPad, on the GPS unit to record data in the field. In my case, it will be used for the collection of data for a microclimate survey of the UWEC campus.


View Feature Class in ArcMAP

To give an idea of what information will look like once it has been collected, open ArcMAP.

Step 1: Open the Catalog in ArcMAP, and locate your newly created geodatabase and feature class (as seen in Figure 14).

Figure 14: This figure shows how to locate your new geodatabase and feature class (selected in blue to the far right of this screen). Simply drag it over to the table of contents to place the data on your map.)

Step 2: Drag your selected feature class to the Table of Contents on the left. From here you can look at the data tables you have created.

Step 3: Right click on your feature class in the Table of Contents to left of the screen and Select Open Attribute Table from the drop-down menu (as seen in Figure 15).

Figure 15: This figure shows how to access the attribute table for your new feature class.

Step 4: The attribute table that opens will contain all of the domains you created when building your geodatabase and feature class (as seen in Figure16). This is where all information will be displayed based on your collection through ArcPad on a GPS unit in the field.

Figure 16: This figure is the table displaying all of the domains you created in your geodatabase and feature class. All data collected in the field will be displayed here as it is collected in the field by inputting it into ArcPad on your GIS unit.


Conclusion:

The geodatabase is an incredibly powerful tool for implementing pre-planning into actual field work. By carefully thinking out the needs of your project, you can build an intricate framework for the collection of data in your geodatabase.

Taking the time to familiarize yourself with building good database structure can be one of your greatest assets in the field. It will help keep you organized, increase efficiency, and improve accuracy of data collection. Without a carefully developed geodatabase, you will leave yourself prone to situations exactly opposite of the benefits it provides.





Sunday, March 2, 2014

Field Activity #5: Development of a Field Navigation Map/ Learning Distance-Bearing Navigation

Introduction:

It is probably very far from most of our minds to think of using a map for navigation purposes beyond looking for exits for the nearest rest stop on a road trip. But, there are many occupations and recreational activities where navigating for something other than highway travel is helpful, and maybe even a necessity.

In such cases, providing users with accurate maps is of utmost importance. Imagine being guided off track in the woods during dangerous weather elements. Real situations like this exist and require map makers to consider the needs of users when choosing what to include and omit in a map.

This is not merely a matter of cramming every potentially useful piece of information into a map. Doing this would provide a very muddled picture to try to follow. The basic elements of map making, visual clarity, legibility, visual hierarchy, balance, and figure-ground are vitally important to consider in every map produced.

This activity requires making two maps for navigation. One map must be projected using the UTM coordinate system while the other must be projected using the world Geographic Coordinate System.

The Universal Transverse Mercator coordinate system divides the earth into 60 zones in six-degree bands of longitude (as seen in Figure 1). It is projected using a secant transverse Mercator projection

Figure 1: Map of the earth overlaid by the 60 UTM zones. Every zone spans 6 degrees of latitude using the secant transverse Mercator projection\
 
 
In addition, I will discuss the basics of navigation using a map and compass.
 

Methods:

Data Collection:
 
Professor Hupy provided several different data features we could choose to include in our maps. It was up to each student to decide which of these features would be the most helpful.
 
There were two sets of contour lines available to us (2 and 5 ft.). I chose to use the 2 foot contour lines because I felt that detailed elevation data would be important considering the varied terrain of the Priory Course.
 
Originally, I had planned to use an aerial image in my map to help orient myself to the area. However, after speaking with Professor Hupy, he mentioned that having a busy map ends up being more distracting and keeps you from being able to take good notes on your map. As a result, I chose to eliminate the aerial image.
 
In order to make sure that I stayed aware of the extent of the course, I included the Priory Course Boundary
 
Map Production:
 
The feature layers mentioned in Data Collection were combined within ArcMAP. For the first map, I chose the most appropriate projection, UTM zone 15, based on the location of our navigation  course. 
 
For the second map, I used the World Geodetic System (WGS) 1984. This is the standard used in cartography and navigation as well as being the reference coordinate system used by GPS.
Based on what Professor Hupy had mentioned about taking notes, I chose to include a note-taking section along with the other necessary map elements like a scale, north arrow, etc.
 
Each map needed to be displayed as an 11x17 figure with a landscape orientation. To do this in ArcMAP, Layout View was selected to display the maps. Then the following sequence was followed Change Layout --> North American (ANSI) Page Sizes --> Tabloid (ANSI B) Landscape.mxd (as seen in Figure 2). For this selection, the default setting is an 11X17 map with a landscape orientation.
The next step was to add the representative grids for meters and degrees to each map.
 
 
 
Figure 2: This figure shows the screen where the template to display your map as an 11x17 landscape oriented image is selected.
 
 
Next, I added the grids to each map in meters and degrees respectively. To do this within ArcMap, I remained in Layout View and followed the following sequence
 
 
Properties --> Grids --> New Grid
 
 
Then, within the Graticule Wizard, I chose Measured Grid (as seen in Figure 3).
 
Figure 3: Within the Graticule Wizard, you can choose which kind of grid you want to be included on your map.
 
 

From there you can move on to select a coordinate system within Properties. You will also be able to set the interval of your grid. For my map shown in meters, I chose a 50m interval on both the X and Y axis, and for my map shown in degrees I chose an interval of .00075 degrees on both the X and Y axis. For the latter interval, it took some trial and error to find the right interval.
 
Originally the numbers were shown inside the grid. This was hard to read as the numbers were displayed on top of the map. Within the Graticule Wizard, I adjusted the placement of the numbers so that they were on the outside of the grid. This made them much easier to read.

Results:

The following maps were produced using the methods above. The first map (as seen in Figure 4) shows the navigation course displayed in the  UTM Zone 15 projection with a metered grid.



Figure 4: This Priory Course Navigation Map contains 2 meter contour lines, a navigation course boundary and a 50 meter interval grid
 
 
The second map (as seen in Figure 5) shows the navigation course displayed using the WGS 1984 coordinate system with a degree grid.

Figure 5: This Priory Course Map contains 2 meter contour lines, a navigation course boundary, and a .00075 degree interval grid
 

Compass Navigation:

One method for navigating using the course maps I have created is a simple compass. While we will have the opportunity to use more sophisticated equipment in later exercises, it is important to be able to implement this basic method in the case of equipment failure.
 
A compass (as seen in Figure 6) will be used in our first navigation exercise.
 
Figure 6: This compass is almost an exact replica of the one we will be using in our future orienteering exercise.
 
 
To use the compass, you begin by placing it on the map of the area you will be navigating. The arrow seen at the top of the compass should be pointed in the direction of or toward the point you are trying to navigate to next.
 
Once this is done, rotate the bevel (rotating housing with degree dial) until ) 0 degrees on the bevel is pointing the direction of north as specified on your map.
 
Removing the compass from the map, you can now adjust your direction until the red end of the magnetic arrow fits into the hollow orienteering arrow. This position is referred to as "red in the shed."
 
As you move, make sure that you maintain this "red in the shed position. This will keep you moving in the direction of the point you are trying to reach.
 
Pace Count
 
Another useful tool for navigation is a pace count. By having a general understanding of your pace count you can keep track of the distance you have travelled from your initial point to the next point you are trying to reach.
 
To establish your pace count walk 100 meters using a consistent and comfortable stride. Simply count each step of ONE of your feet (not both). My pace count was 66 strides over the 100 meter distance which is fairly standard. Most pace counts will be in the 60s. To ensure accuracy, walk the distance 2-3 times and take the average of your pace counts from each trial.
 
One method recommended to us in our training was to break off a piece of a twig  and put it in your pocket each time you walk 100 meters. If you become unsure of how far you have travelled you can just count the number of twigs you have broken off.
 


Discussion:



I avoided the temptation to include a lot of features in my map, namely an aerial image. This may or may not turn out to be a good idea. For a seasoned navigator, I assume it would be no problem. I cannot count myself as one, though. This may lead to difficulty in the field, if I happen to get lost/disoriented.

I am also unsure of the impact of 2 ft. contour lines vs. 5 ft. contour lines. If the 2ft. distance isn't useful, that I will have made my map busier for no reason. As I begin to think about the wide area of the course, I am apprehensive about my choice, and wonder if 5 ft. contours might not have been a wiser choice.

I spent some additional time talking with our trainer to make sure I understood the whole process of how to operate the compass effectively. This was not second nature to me. After going through the process a couple more times, I felt more confident that I would be able to carry out this process in the field.

Conclusion:

Creating maps for navigation purposes must take into account several things. The things I noted were the level of experience of the person using the map, the overall area encompassed, the level of topographical change, and the need to take notes.

It is quite possible that someone with greater experience would desire an entirely different map than the one I would create for myself. Also, the size and topography are going to effect the ideal intervals used for contour lines and gridlines.

The key really is to make sure you are taking into consideration anything you can think of when preparing navigation maps. Over time, you will learn to ask better questions, and will better understand the needs of those using navigation maps. I would guess that, after going through the orienteering exercise, I will have added insight for creating my next navigation map.